In the cervical spine, the combined ossification of the ligamentum flavum (OLF) and ossification of the posterior longitudinal ligament (OPLL) is rarely seen. Patients are usually treated with cervical laminectomy or laminoplasty with OLF resection. In most of the cases, OLF is adhered to the dura and there is a risk of dural tear or cerebrospinal fluid (CSF) leakage during its resection. In this case report, authors present results of laminectomy with debulking instead of complete excision of OLF for spinal cord decompression in a cervical myelopathy case where OLF was adhered to the dura. A 69-year-old man presented with insidious-onset weakness in bilateral lower limbs and unsteady gait since 1 month. He had a history of neck pain with left upper limb radiation for 2 years. Magnetic resonance imaging (MRI) showed C5 to C6 severe central canal stenosis with underlying myelomalacia. Computed tomography (CT) showed OPLL and OLF contributing to severe central canal stenosis at C5 to C6 level. Patient underwent C4 to C6 laminectomy, debulking of OLF, posterior instrumentation, and fusion with autogenous bone graft from C3 to C6. Histological specimen showed osseous tissue within the ligamentum flavum. After surgery, patient’s symptoms improved, and no recurrence was observed at 4 years after surgery. The symptoms of myelopathy were successfully treated with debulking instead of complete excision of OLF, thus reducing the risk of dural tear or CSF leakage.